1. Field
Embodiments of the present invention relate to a secondary battery.
2. Description of the Related Art
A rechargeable, secondary battery may be charged and discharged unlike a primary battery that may not be recharged. A low capacity secondary battery that comprises a pack shaped battery cell may be used as a power source for various small portable electronic devices such as cellular phones or camcorders. A high capacity secondary battery that has several tens of the battery cells that are connected may be used as power sources for driving motors such as an electric scooter, a hybrid automobile or an electric automobile.
The secondary battery may be fabricated into various shapes including a cylindrical and a prismatic shape and may include an electrode assembly including a positive electrode and a negative electrode and an insulating separator that is interposed in between the electrodes and is inserted into a case. The case is mounted with a cap assembly. In the secondary battery, when the internal pressure of the batteries rises above a predetermined level due to excessive pressure generated by overcharge or an electrolyte is decomposed, a danger of fire or explosion results.
Accordingly, there is a need for a secondary battery having improved safety.